The present invention relates to relief valves and more particularly to an excess flow volume control shut off valve.
1. Field of the Invention
The flow volume of a fluid through conductors is preferably maintained at or near the limit of flow compacity of the conductors or vessels to which the fluid is being injected. Sometimes the downstream conductor or vessel breaks resulting in the loss of fluid through the hole in the conductor or vessel. There is a need for stopping the volume of flow in case of a brake in the flow line or vessel. This invention solves this problem.
2. Description of the Prior Art
U.S. Pat. No. 5,318,060, issued Jun. 7, 1994, to Taylor for, "FLUID FLOW VELOCITY EMERGENCY SHUTOFF VALVE", and U.S. Pat. No. 5,373,864, issued Dec. 20, 1994, to Taylor for, "DOWN STREAM LOW FLUID PRESSURE EMERGENCY SHUTOFF VALVE" are believed good examples of the state-of-the-art U.S. Pat. No. 5,318,060, features control of flow velocity impinging on a valve disk in a the flow line and when the fluid velocity reaches a predetermined limit it moves the valve rod longitudinally to seat the disk valve and stop fluid flow through the valve. The other U.S. Pat. No. 5,373,864, features a similar disk valve in a flow passageway which is maintained off seat by a spring during under normal fluid flow impinging on the disk valve, but releases the spring to close the disk valve with its seat in the event fluid pressure in the flow passageway falls below a predetermined minimum.
This invention is believed distinctive over both of these similar patents, by providing a relief valve which features a conically shaped member axially moveable longitudinally in a fluid flow passageway. When the fluid volume across the conical member generates a predetermined pressure drop, across the position of the conical member fluid bypass, a piston valve moves longitudinally downstream and collapses a slender column normally maintaining the piston valve in fluid flow position.